Every week this build gets more and more interesting as we dive deeper into the inner workings o the Subaru BRZ and Scion FR-S platform. Last week we took a look at the first step in our build process:reinforcing the chassis by seam welding the structural body components.For this installment, we peel back the layers of the engine to understand what we have to work with, and where it can be improved in relation to our initial build objectives. As with any good build, you define an objective based on what you have to work with. In order to properly understand what we had to work with first hand, it was necessary that we dive into the platform’s heart. This time, we turned toSCR Performancebecause of their intimate knowledge of Subaru drivetrains, as well as their reputation as top engine builders. We knew they would give an accurate assessment of what areas we’d need to address as the build progresses.

WhileProject BRZwas off getting work done on various other components (seam welding, suspension assessment, etc.), our donor engine arrived at SCR for teardown and assessment. SCR requested we source a used engine so they could properly analyze and assess the stock platform’s weaknesses and wear points. We liked this idea, as a used engine would show any potential weak points since it has been exposed to the wear and tear of every day abuse, and can tell expert builders what they need to look out for when adding more power.

Once the donor engine, with 18,000 miles on the clock, arrived, SCR immediately started tearing it down and documenting what they found. All of the information provided in this article came from SCR’s direct assessment, as well as several conversations with other key industry personalities. We’ve broken down the assessments into the following major component groups: bottom end, top end, fuel, ignition, oil and cooling.

FA20 / 4U-GSE ENGINE SPECS

Before we tear it apart, let’s have a quick refresher on the stock motor we’re dealing with.

• Engine Code: Subaru – FA20/Toyota – 4U-GSE

• Developed from the FB engine (Subaru Forrester)

• Developed with goals of weight reduction, while maintaining durability

• Horizontally opposed (boxer) 4-cylinder dual overhead cam engine

• 1998cc, square 86mm bore and 86mm stroke

• Toyota’s D4-S injection system (port and direct injection)

• AVCS (Active Valve Control System)

• Compression Ratio: 12.5:1—very high value rarely found on production engines

• Redline – 7,450 rpm

• Power Output – 197hp @ 7,000 rpm, 151 lb-ft @ 6,400 rpm

Subaru did an impressive job of cramming a lot of technology and capability into a potent little package. This gives us a lot to work with as we get ready to wring out a lot more power from our FA20!

INITIAL TEARDOWN

As SCR tore down the engine, they gave us their thoughts on what they found. Though it did have just 18,000 miles, there was no sign of excessive wear on bearings, sides of the pistons, cylinder bores and crank journals. Not too surprising, but if any areas of concern were rearing their heads that would be a focal point for us to address during the build.

FA20 / 4U-GSE BOTTOM END AND ROTATING ASSEMBLY

The heart of the powerplant is the block, which is unique to the FA/FB series of engines, and features an open deck design. On other motors, they will cast the block out of solid billet or similar material and then drill out the ports and passageways into it, forming what is called a “closed deck.” On the FA, they cast all these voids in for the oil and coolant as it’s a more cost-effective process, and keeps the weight down, though the tradeoff is reduced cylinder pressure support you would require for high-performance applications. When the air fuel mixture ignites, you have a huge pressure spike in the cylinder and combustion chamber, and the forces are pushing at all angles. Something is going to give eventually if enough pressure is applied. Since we plan to add forced induction, you can certainly understand why this is an area of concern for us.

Fortunately, there are some options available. Though this is a bit low-tech, some drag race motors have the coolant passages filled with concrete to make a solid block. This adds strength to the cylinder walls, but obviously isn’t realistic for a performance application that runs further than a quarter mile at a time. We aren’t doing that. The other, more refined and accepted option is to employ sleeve inserts. The stock FA20 has thin iron liners that act as a friction surface (similar to a bearing) to keep the piston rings from wearing directly on the aluminum cylinder walls.

For our build, SCR doesn’t feel it’s necessary to re-sleeve the block based on theobjectives we developed. They are basing that assessment on what others builders have accomplished so far. Case in point, Full Blown is already claiming 700hp on the stock bottom end. Not too shabby.

These motors seem to be making serious power, but the longevity is what’s in question. What’s the failure point? What’s going to eventually fail at those bigger power levels? We are still waiting to see as there are several companies pushing the envelope. Fortunately, the FA20 is proving to be pretty strong, even when laying down some pretty big power numbers.

SCR didn’t find too many surprises with the crankshaft, but did find one item of note. Compared with the EJ-series cranks, the FA has thinner rod and main bearings because the engine wasn’t designed to produce the power levels of the EJ. The engine was designed to be high-revving and efficient, which the thinner bearings help with. Keep in mind that, anytime you reduce friction surface area, you reduce drag, leading to more efficiency of the rotating assembly.

Subaru has done a good job of producing a very high-quality bearing used on the crankshaft and rods. SCR doesn’t see any reason to put a different bearing material or change the tolerances.

The rods have a fairly unique feature found in boxer-style engines. While most rod caps are cut at a straight angle, the FA20’s rod caps are angled, which allows you to remove the rods and pistons without splitting the case halvesvery handy for limiting time during maintenance and upgrades.

Another key point is that Subaru cast the rod as a full assembly, scored the rod, then used an impact to break apart the cap from the rest of the rod (this maintains the natural grain of the metal, stronger design). This process not only yields a stronger design, but also reduces production cost; best of both worlds for the manufacturer. Be sure that you don’t mix the rods and caps up in any way when reassembling the bottom end as they fit together like a puzzle!

The piston ring gaps are pretty small at the top and the lower ring gap is quite a bit wider than what SCR is used to seeing (compared to the EJ-series). The thought is the small gap up top prevents compression loss and the larger gap at the bottom allows for gasses to escape into the crankcase, and not build up between the rings.

When it comes to the pistons, we’re actually going to rely on our partners at Crawford to help us out with that information. They’ve already done the R&D and have designed a custom set of pistons that are different than all the other off-the-shelf products. They’ve gone above and beyond to redesign the part, having changed pin locations and rod lengths to get better rod ratios, and reduce piston side loading on cylinder walls to help the engine work more efficiently and rev up quicker to perform the way they want it to. It’s important that we address the ring gaps specifically for our application, as it will certainly change due to the fact that the engine will now be turbocharged.

One thing SCR noticed during disassembly was the excessive use of sealant–Subaru used an absolute ton of it. While Subaru did their best to make sure the engine wasn’t going to leak any oil, it certainly made it difficult to disassemble. SCR had to cut the sealant, working all the way around the perimeter of the part just to separate it. This proved VERY time intensive to separate and clean the components of all the sealant.

SCR speculated Subaru didn’t want to use a composite gasket as it becomes a failure point. Subaru has a fairly good track record to support their decision, though, as all EJ-series Subaru motors have sealant in between the block halves, and you hardly ever hear about leaking there. It’s basically two machined surfaces with sealant: so there’s no way it can develop a leak unless there’s been excessive force or improperly applied.

FA20 / 4U-GSE TOP END AND VALVETRAIN

As SCR learned, cylinder head removal has a few extra steps with the FA20. To get the cylinder heads off the engine, you actually have to pull the cam bridges off since they block all access to the head bolts. Common sense will tell you that you can’t physically remove the head until you have access to the bolts. There is some silver lining, though, as the cam bridges are actually a modular setup that keeps the cams in their cam bearing journals when you remove the bridges.

Subaru has transitioned to a roller rocker-style, cam lifter design, which helps reduce a friction point in the valve train. Since it’s still a solid lifter design, it’s something that, over time, will need adjustment to keep within spec. Unfortunately, the cam bridges rear their ugly heads again as you have to remove them if you want to adjust the valve clearances.

The intake ports look generally large when compared to the normal EJ-series, but we won’t know for sure until we run the heads on a flow bench to obtain the necessary data. As wementioned in a previous article, the factory intake manifold no longer has a pesky TGV like the old EJ-series and FB motors, since a premium was placed on smooth airflow to support the higher-revving nature of the FA20.

Continuing upstream, the high-pressure fuel injector is pretty similar in design to the rest of the industry, so nothing earth-shattering there. Between the multi-port and direct injection, they can get a better mixture of the fuel and air based on driving situations, giving more of a complete burn. Each of the different fuel systems has their own benefits and weaknesses allowing Subaru to exploit the best of both worlds. The direct-injection provides better fuel atomization under heavier loads, while the port injection helps to manage carbon build-up at lighter loads and idle.

Direct-injection systems require a high-pressure fuel feed (in the thousands of PSI), and generally you need mechanical assistance to elevate pressure to those levels. The FA20s pump is mechanically driven off the camshaft via three-lobes, so in one revolution it strokes the fuel pump three times. This takes fuel pressure from the electric in-tank pump from about 60 PSI to the needed thousands of PSI.

An oil-actuated system (ACVS for Active Control Valve System) allows for near continuous camshaft adjustment to offer the most power for a given throttle position and rpm. Both the intake and exhaust cams can alter their relation to the crankshaft, and the whole show is monitored by the ECU.

Speaking of the camshafts, SCR noted they have nice big fat lobes, so they may not be something we need to worry about swapping out. Couple that with the near infinite adjustability of the cam timing, and there may not be much need to put big aftermarket cam shafts in to get the power.

As SCR stepped into the combustion chamber, they noticed there is not a whole lot of clearance between the valves and the pistons. If you’re trying to go with cams that have higher lift and/or duration, you could potentially have interference issues.

The valve stems are pretty small on these motors to help out with air flow as the smaller diameter takes up less space in the intake and exhaust ports.

In the name of efficiency, lightweight valve springs are employed so the engine isn’t fighting against its own components to operate. However, because the springs are so light, they could have issues closing the intake valves when they are fighting against 30lbs of boost trying to cram into the combustion chamber. This is an area we are looking to address.

FA20 / 4U-GSE IGNITION SYSTEM

As with most newer performance vehicles, coil packs are used on each cylinder to control spark. This is a big advantage for tuning as ECU’s are so fast they can really utilize the independent coil packs, and direct injection, to essentially tune each cylinder independently.

If we have issues with blowing out the spark, we can always hook up an amplifier to boost the signal, but the kits are designed for a hot, heavy spark, so right now we don’t see the need to upgrade.

FA20 / 4U-GSE OIL & COOLING SYSTEMS

Since additional oil pressure is required for the variable cam timing system, the standard oil pump was designed with plenty of flow and is actually a fairly robust unit. We don’t see ourselves upgrading to a larger pump for our build.

FA20 / 4U-GSE OIL PAN

The FA utilizes an upper and lower oil pan where the upper is actually a functional component of the bottom of the block. On the EJ-series, it’s not a two-part component. The “upper oil pan” completes the bottom part of the block, while the “lower oil pan” is generally small if looked at by itself. However, the upper oil pan will also contain a considerable amount of the oil capacity. The small lower oil pan also acts as a funnel since the pickup point is very precise. Encountering g-forces commonly found on race tracks will begin to cause issues with this design. A larger oil pan with baffling will allow you to not worry as much about waiting for the oil to drain from the heads while pulling some serious g’s.

If you are looking to turbocharge your FA20 like we are, you need to consider how you will get oil to the turbocharger. If you are working on a budget, you will need to add a port to the oil pan for a turbo oil drain line. Sounds easy, but placement can be very important (especially on a small volume pan like the FAs), and they can be more prone to leaks. It may be best to source an aftermarket pan that was designed specifically for turbocharged applications that have increased volume and careful consideration of return line placement.

Last but not least, SCR evaluated the radiator and associated cooling components. While the stock radiator seemed up to the task of keeping a stock, or mildly tuned engine, at a safe operating temperature, we’re ditching it in favor of one with more capacity. It may not necessarily need a larger unit, but with the power we expect the engine to make, along with mounting an intercooler in front of it, we want to ensure we won’t encounter any cooling problems whether we’re on the track or sitting in line to get into a show.

Fortunately, the rest of the cooling system was deemed OK as the water pump can flow plenty of fluid, and the stock heat-range thermostat will most likely be fine. There are companies that can provide a lower-temp thermostat, but typically you want to have the engine running at the right temp as it will help with proper atomization of the fuel.

That surely was a mouthful, but we feel this was one of the most important articles in our entire BRZ / FR-S Performance series. Now that we understand the strengths and weaknesses of the platform’s powerplant, we can start to address those items with upgrades. Next week we’re postponing our documentary article to the following week as the team will be in Houston for TX2K14. In that installation, we will take a look at our new Air Lift Performance suspension with an overview, unpacking, and analysis (visual inspection and comparison)! Since we got our hands on it, and are able to measure clearances and adjustability, we’ve developed a specific build plan that we know you’re going to love!

I drove over 10,000 miles in the hot weather as high as 110 degrees to cold as low as -1 degrees freezing condition, along with several autocross events on the weekend with these brake pads.
These brake pads work as a double duty pad for daily driving and autocross and have exceed well over my expectation.
They work reliably well for everyday street driving, with added confidence in pedal feel, and resulting in better control.
The W2 provides excellent stopping power for street tires and with significantly less dust than most performance pads of this type.
The pads don’t fade much in most casual sporting activities, and they lack any of the associated noises or dusting of other typical performance oriented pads.
While it isn’t a fully geared competition brake pads for road racing circuits, what you get in exchange is all of the better characters of street car pads in terms of life expectancy, wear, reliability and huge operating range.
I’ve tested them in variety of climates and conditions, and the W2 pads kept evenly, excellent feel and modulation, to delicately tread snow, or hard brake in the dry.

I would recommend to anyone seeking casual performance pads, which can retain the clean and quiet nature of OEM pads while seeking extended braking control and resistance to fade under mild sporting driving.
Winmax USA does make a very good product according to my needs

This year, we had lovely 86Fest! This one was at Irwindale Speedway. Started out in cool temperature, but that changed quickly. I learn by lesson from day before (SubieFest) and wore a tshirt!

A lot of vendors came to this event. Washington to Florida, all over the US to show cool parts for the twin. I gotta say, I saw some pretty cool ones, like these FR-S from Scion Racing & GReddy

Of course, OEM showing off new Scion FR-S RS1.0 at their booth. I still have mix feeling about this, but let’s not go there.

& some of you guys might seen this FR-S. Any guesser?

It was awesome event… but some of us were there for both SubieFest & 86Fest, back to back isn’t easy for some of us… like this guy lol I almost did the same, but all the goodies all the vendor had on their table kept me walking around talking and take pics.

Now, instead of showing off all the cool twins & how you guys missed the awesome event, I thought to share some cool parts I saw at the event. Just making sure anyone thinks that I get paid to showing off these parts, just remember this I DON’T GET PAID! I don’t get penny from any of these brands sell more from members buying it.. I’m just sharing some goodies with you guys. THAT’S ALL

AVO Turboworld Oil Cooling Duct

AVO Turboworld finished cooling duct just in time to show off this parts at the event. It’s kinda hard to see from the front, so here’s the side pics.

At first, I thought it was going into where BRZ’s foglight goes… but Paul from AVO Turboworld corrected me wrong. It goes next to intercooler and it can fit on both FRS or BRZ… I was still confused, so he show me on his car & it made total sense. I took some pics, instead of explaining it.

It’s kinda hard to see it, but can you see it on the left corner? Here’s a closer pic.

As you can see, it works for both NA or FI. He told me that, it should work on most of intercooler (please double check with them if it works on your intercooler).

Beatsonic Blaid Antenna

I don’t think, I need to explain bout this. It’s literally an antenna. Now, how does it look on the car? Here’s Beatsonic’s demo car with this antenna.

I so love Eric’s FR-S, looks sweet… anyways. I’ll be honest, I don’t think it’s not for everyone. Some will say too big or looks ugly, some will like the look or like to be different from others… or couldn’t resist the words like “Limited Edition”. For me? I think, this pic will answer the question.

I’m a sucker for a words like “Limited Edition” or “Special Edition”, can’t help it. This antenna was only sold this year’s 86 / BRZ Style Fest in Fuji Japan. I had a option to go with ver 2 or this, but I had to go with this. If you’re like me, it is limited edition, so when it’s gone, it’s GONE~

I’ll do small review later, but for now, I’m kinda tempted to wrap it or plastidip my whole car red and make it look like this… or any BRZ owner that have Lightning Red that have this antenna please post here with that pic, thanks

FT-86 SpeedFactory UEL Header

When I say these guys are popular, I’m not joking. There are always someone coming over checking their goodies they brought with him. I should of went there in the morning when people were still parking (that’s when I took this pic).

Of course, they brought Jeremy’s newly design FRS with them (which btw won last year’s 86EXPO Autox). I must say, white, black & dark pink combo is pretty cool.

With all the goodies they brought, this part of the table caught my attention, look this all the headers!

Within all the shiny header, I saw something that everyone is talking bout in Engine, Exhaust, Transmission section of the forum.

Some of you waiting few/several months, yes, it’s not a dream, it’s actually do exist. Yo himself grab that FT86SF’s UEL header to show it to me. I was pretty surprised on the quality. Yes, true that, it’s not shiny as Tomei or other headers… but how often you buff your header shiny? They have dyno’ed it and other have dyno’ed it to prove this header is AWESOME! Inside was very clean to make sure the smooth flow out.

Again, thanks Yo for his time, even though it was extremely busy and HOT!

Cusco USA Touring A Shock Absorbers

Of course, Cusco USA was there (both days) to show some cool parts for the twins. One of the new release parts was this.

Cusco USA always had Touring A Shocks. They have them for all the Subaru cars: Impreza, Forester, Legacy, WRX, STI, you name it, they have it. This time around, they brought it to the twins. You don’t want to go with coils, but want some damper control or just want something bit more sporty feel from stock? This is way to go.

Thanks ModBargains for taking their time to talk with me and it was pleasure to talk with you guys.

There were so many other vendors: Rays, GReddy, Borla, Cosworth, Apexi, Seibon, Winmax, Injen, Works, FRSports and list goes on and on. If you guys didn’t go or was debating on going, this is something to look into.

Also special thanks to Hachiroku for taking his busy time to have a dinner with me.